LAUSR

Evidenc e exists for ventricular fibrillation (VF) waveform hanges over time as reflection of the metabolic status of the yocardium during cardiac arrest and cardiopulmonary resusitation (CPR) [1]. Thus, quantitative electrocardiogram (ECG) aveform analysis during CPR might represents a potential optimal oninvasive guide toward identification of priority of intervention, .e. chest compression or defibrillation, having proven high accuacy in predicting success or failure of defibrillation attempts [3,4]. mong the different VF waveform parameters, amplitude spectrum rea (AMSA) has emerged as one of the most accurate predictor f defibrillation outcome [5]. Generally, in multiple observational tudies, higher AMSA has been associated with higher rates of terination of VF and return of spontaneous circulation (ROSC), while ower values predicted failure of resuscitation efforts [3,6,7]. Hypohetically, chest compression should be performed until AMSA is eemed to be favorable for a defibrillation, limiting the interrupions for delivery of failing shocks [5]. Nevertheless, such a real ime VF analysis-guided CPR has not been validated prospectively et. The upcoming AMSA trial (NCT03237910) should address this eed. Interestingly, while we are still awaiting for a confirmation r a disconfirmation of the property AMSA was conceived for, i.e. rediction of defibrillation success [8], recent retrospective analyes are introducing new uses and “predictive” capabilities of such VF parameter. In this issue of Resuscitation, Dr. Hulleman and colleagues have resented an elegant retrospective analysis of AMSA during CPR, iming to investigate its association with the presence of acute T-elevation myocardial infarction (STEMI), as cause of the outf-hospital cardiac arrest, and/or with previous MI and survival [9]. he study was performed in a large database including more than 00 patients from the ARREST (AmsteRdam REsuscitation STudes) prospective registry, which enrolls all resuscitation attempts n the North-Holland province of The Netherlands [10]. AMSA as confirmed to be higher for patients surviving to hospital disharge compared to non-surviving ones. Of interest was the lower MSA measured in patients with STEMI compared to those without TEMI, which led to the loss of AMSA capability to predict surival to hospital discharge. Indeed, the absence of rises in AMSA uring CPR, despite increases in coronary perfusion pressure, was